/// <reference lib="webworker" />
import { argon2id } from 'hash-wasm';
import { POW, proofMessage, type Challenge } from '../shared/protocol.ts';

self.onmessage = async (event: MessageEvent<{ challenge: Challenge; owner: string; duty: number }>) => {
  const { challenge, owner, duty } = event.data;
  try {
    const salt = new Uint8Array(challenge.seed.match(/.{2}/g)!.map(x => parseInt(x, 16)));
    let nonce = crypto.getRandomValues(new Uint32Array(1))[0];
    let attempts = 0;
    const start = performance.now();
    for (;;) {
      const tick = performance.now();
      const hash = await argon2id({ ...POW, password: proofMessage(challenge, owner, nonce), salt, outputType: 'hex' });
      attempts++;
      self.postMessage({ type: 'progress', attempts, hash, rate: attempts / ((performance.now() - start) / 1000) });
      if (hash.startsWith('0'.repeat(challenge.difficulty))) {
        self.postMessage({ type: 'found', hash, nonce });
        return;
      }
      nonce++;
      await new Promise(resolve => setTimeout(resolve, Math.max(20, (performance.now() - tick) * (1 / duty - 1))));
    }
  } catch (error) {
    self.postMessage({ type: 'error', message: error instanceof Error ? error.message : 'Mining worker failed' });
  }
};